Non-volatile memory (e.g., flash memory) based data storage devices have become mainstream in the past decade. Flash memories use non-volatile memory cells such as electrically-erasable programmable read-only memory, (EEPROM), but are not randomly accessible at the byte level. Instead, whole pages or sectors of 512 bytes or more are read or written together as a single page. NAND flash memory is commonly used for data storage of blocks. Pages in the same block may have to be erased together, and limitations on writing may exist, such as only being allowed to write each page once between erases.
Data transfer operations (e.g., read/write) are performed with electrical signals between host and NVMDs. Due to the nature of electrical signals may be lost or corrupted during data transmission. Therefore, data may contain random errors when stored or retrieved from non-volatile memory. There are many prior art approaches to overcome data error problems. One of which is to use error correction code (ECC) such that additional error correction information is carried along with the real data. However, the prior art approaches are very complicated hence expensive and not optimized. Therefore, it would be desirable to have an efficient and effective implementation of error correction to ensure data reliability of a non-volatile memory device (NVMD).